This invention relates to a joining apparatus, and more particularly, to a joining apparatus for use in the splicing of photographic film.
It is known in the art to join pieces of photographic film or other material one after another to form an elongated assembly which is suitable for development or other purposes. In the splicing of photographic film, the rear edge of a preceding piece of film and the front edge of a succeeding piece of film are positioned on a joining table. A heat sensitive joining tape is applied onto the adjacent edges of the two pieces of film, and a heating head is lowered to heat the joining tape under pressure. The joining table has an upper surface covered with a material which prevents the fusion or adhesion of the adhesive in the joining tape to the joining table. For this purpose, it is customary to employ, for example, a release agent containing a fluororesin, such as Teflon (TF), as a base. When the heating head is lowered onto the stationary joining table, however, it is sometimes difficult to ensure parallelism of the mating surfaces, since the film and the joining tape are present therebetween. This can also happen if the apparatus or its installation lacks dimensional accuracy. Accordingly, the fusion preventing material on the joining table is often likely to be partially worn, or otherwise deformed, resulting in malfunctioning of the apparatus. It is, for example, imperative to change the fusion preventing material frequently in order to ensure satisfactory operation of the apparatus.